Eclipse Not Finding com.sun.tools

This is really simple and obvious but took me a while to work out.  I had a maven project which Eclipse would open but one of the maven dependencies has a child of

    <dependency>
        <groupId>com.sun</groupId>
        <artifactId>tools</artifactId>
    </dependency>

The maven plugin couldn't find this dependency and as a result wouldn't build the project, show compilation errors or build unit tests.

It turns out that a recent java installation had changed the path environment variable to put

    C:\ProgramData\Oracle\Java\javapath

at the front of the PATH variable.  The contents of this folder are shortcuts to the runtime (JRE) environment.  This means that when I was starting Eclipse it was running a jre and not a jdk.  Sorting out the PATH environment variable and moving the offending new entry to the end meant that I was using my own JAVA_PATH again which was pointing to the jdk.  Restarting Eclipse then meant that the problem was sorted.

Mocking Static Classes with Powermock

I always forget how to do this and have to look it up every time so here is a quick example for future reference!

- Annotate the class with @RunWith(PowerMockRunner.class)
- Annotate the class with @PrepareForTest(<class-to-mock>.class)
- Mock the static in @Before or in @Test PowerMockito.mockStatic(<class-to-mock>.class)
- Set expectations with when(<class-to-mock.class>.something()).thenReturn(something_else)

Example

This is a simple example which mocks StringUtils (apache commons-lang3).  This shows that the StringUtils.isBlank() method can be mocked to return different values.

    import static org.junit.Assert.assertFalse;
    import static org.junit.Assert.assertTrue;
    import static org.mockito.Mockito.when;

    import org.apache.commons.lang3.StringUtils;
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.powermock.api.mockito.PowerMockito;
    import org.powermock.core.classloader.annotations.PrepareForTest;
    import org.powermock.modules.junit4.PowerMockRunner;

    /**
     * An example of using powermock to mock a static class.
     */
    @RunWith(PowerMockRunner.class)
    @PrepareForTest(StringUtils.class)
    public class ExampleTest {

        /**
         * Test blank when mocked to return that an empty string isn't blank!
         */
        @Test
        public void testBlankMocked()
        {
            // Arrange
            PowerMockito.mockStatic(StringUtils.class);
            when(StringUtils.isBlank("")).thenReturn(false);
        
            // Act
            final boolean blank = StringUtils.isBlank("");

            // Assert
            assertFalse(blank);
        }
    
        /**
         * Test blank using the standard non-mocked behaviour.
         */
        @Test
        public void testBlankNormal()
        {
            // Act
            final boolean blank = StringUtils.isBlank("");

            // Assert
            assertTrue(blank);
        }
    }

Maven Dependencies

The powermock dependencies used for this test are,

    <dependency>
        <groupId>org.powermock</groupId>
        <artifactId>powermock-module-junit4</artifactId>
        <version>1.6.5</version>
        <scope>test</scope>
    </dependency>

    <dependency>
        <groupId>org.powermock</groupId>
        <artifactId>powermock-api-mockito</artifactId>
        <version>1.6.5</version>
        <scope>test</scope>
    </dependency>

Angular JS Directive For Decimal Places

Here is a simple example for creating an Angular JS Directive.  In this particular case the input is limited to two decimal places but other code could be created here to limit the input in other ways.

Angular Directive

The directive is in javascript and needs to be imported into the page.

(function() {
    'use strict';

    angular.module('myApp').directive('limitedDecimalPlaces',['$filter', function ($filter) {
    return {
        require: 'ngModel',
        link: function (scope, element, attr, ngModelCtrl) {

            if (!ngModelCtrl) return;

            function round(value)
            {
                return Math.floor(value * 100) / 100;
            }

            ngModelCtrl.$parsers.push(function (value) {
            var cleanValue = value;
                if (value != value.toFixed(2))
                {
                    cleanValue = (value) ? round(value) : value;
                    ngModelCtrl.$setViewValue(cleanValue.toString());
                    ngModelCtrl.$render();
                }
                return cleanValue;
            });
        }
    };
}]);
})();

The ngModelCtrl is the model controller for this angular input.
$parsers is an array of the parsers that are applied to this input.  $parsers.push adds the function to the array (push is a standard Arrays.push() javascript function)

ngModelCtrl.$setViewValue(...) sets the value into the view part and must be a string.  Overall the function rounds the number to two decimal places if necessary and assigns it to the cleanValue.  This is then set into the view and returned so that the model is updated.  Whatever is returned from this function is what is set into the model.

Usage

The standard input can have this directive added to it so that the validation is wired into the input.

    <input type="number" name="myNumber" ng-model="myNumber" limited-decimal-places>

AEM Sightly Templates

When repetitive code is used within an html page, such as capturing an address, using a Sightly Template is really useful to avoid unnecessary duplication and improve maintenance.

Template

The template can be created at the top of the page as

    <template data-sly-template.address> 
        <div class="address">
            Street:  <input type="text" name="street">
            <br>
            Town: <input type="text" name="town">
            <br>
            Postcode: <input type="text" name="postcode">
        </div>
    </template>

Usage

The template usage is very straight forward.  Simply use the Sightly 'call' function,

    <div data-sly-call="${address}"></div>

Separate File

As templates get bigger or for maintainability a separate file can be used.  AEM will do the work of gathering the template files together for a given page so there is no problem about the paths in AEM being available.

To use a separate file the template must be imported in the html page and then called with the extra selector which defines the file it lives in

address.html
    <template data-sly-template.address> 
        <div class="address">
            Street:  <input type="text" name="street">
            <br>
            Town: <input type="text" name="town">
            <br>
            Postcode: <input type="text" name="postcode">
        </div>
    </template>

Import

Import the template file

    <div data-sly-use.details="address.html"></div>

Use

The usage changes very slightly as it has to reference the import ('details') as well as the template ('address') within the file.

    <div data-sly-call="${details.address}"></div>

Using Parameters

Parameters can also be used within a template.  This is useful if you want the template to behave a particular way or if you want to name the fields slightly differently for each instance of the template.

    <template data-sly-template.address="${@ instance}"> 

        <div class="address">

            Street:  <input type="text" name="${instance}Street">
            <br>
            Town: <input type="text" name="${instance}Town">
            <br>
            Postcode: <input type="text" name="${instance}Postcode">
        </div>
    </template>

Here the instance of the template is passed in so that each of the fields can have a unique name even if the template is used multiple times.  In the example below the Invoice address and Delivery address can have different instances and therefore different names for the fields.


    <div data-sly-call="${details.address @ instance='InvoiceAddress'}"></div>

    <div data-sly-call="${details.address @ instance='DeliveryAddress'}"></div>
This usage of sightly to generate templates can be very useful.

AEM QueryBuilder

Here are some examples for using the AEM QueryBuilder.  This took me a bit of time to get used to so it is worth the memory jogger!

Basic Structure

The basic structure uses the AEM adaptTo() to get a QueryBuilder object.

Here the session and builder classes are obtained.  The Query is created with the map of search values (see later).  The SearchResults object would by default be paginated so setting the query.setHitsPerPage(Integer.MAX_VALUE) means we get everything we want.  An iterator is obtained so that we can loop through the results and convert to JSON or further filter if necessary.

    final Session session = request.getResourceResolver().adaptTo(Session.class);
    final QueryBuilder builder = request.getResourceResolver().adaptTo(QueryBuilder.class);
    final Query query = builder.createQuery(PredicateGroup.create(map), session);
    query.setHitsPerPage(Integer.MAX_VALUE);
    final SearchResult result = query.getResult();

    // Iterate over the results
    final Iterator<Resource> resources = result.getResources();

Query Map

The map of values is used to create a PredicateGroup.  This is a group of Predicate objects which are used to match the JCR values against.  The names of the properties will define the predicates that are created for that value.

Create a map to hold the search values.

    final Map<String, Object> map = new HashMap<>();

The 'type' uses the TypePredicate

    map.put("type", "nt:unstructured");

The 'path' uses the PathPredicate

    map.put("path", "/content/mysite/mypages");

The 'boolproperty' defines a JcrBoolPropertyPredicate check. If the search is for 'false' then this is correct if the value is 'false' or not present at all.

    map.put("boolproperty", "live");

    map.put("boolproperty.value", "true");

A numeric range check is possible using the 'rangeproperty'.  This uses the RangePropertyPredicate. There are options for the lower and upper bounds.

    map.put("rangeproperty.property", "age");
    map.put("rangeproperty.lowerBound", age);
    map.put("rangeproperty.lowerOperation", ">=");
Note: even though this is numeric the value provided here should be a string

A number of properties can be matched against.  You can prefix with a #_ to allow multiple properties to be matched on.  These values use a JcrPropertyPredicate

    map.put("1_property", "firstname");
    map.put("1_property.value", "fred");
    map.put("2_property", "surname");
    map.put("2_property.value", "bloggs");

Debugging

Get the Iterator from the PredicateGroup and loop through to see which Predicates have been created for your map.

Always add the values into the map as strings otherwise the predicates don't match.

Use the query debugger to check your map,

    http://localhost:4502/libs/cq/search/content/querydebug.html

AEM Unit Testing

AEM Unit testing of java code can be a bit of a pain.  Here is an example search servlet and the unit test that goes with it.

Servlet

This is a really simple servlet which searches for resources on a particular path

import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.logging.Logger;

import javax.management.Query;
import javax.naming.directory.SearchResult;

import org.w3c.dom.Node;

/**
 * Servlet that can be used to search for nodes flagged as current = true on nt:unstructured nodes.
 */
@SlingServlet(paths = "/bin/search/current", methods = "GET")
public class SearchCurrentServlet extends SlingSafeMethodsServlet
{
    /**
     * Default serialisation.
     */
    private static final long serialVersionUID = 1L;

    /**
     * Logger.
     */
    private static final Logger LOG = LoggerFactory.getLogger(SearchCurrentServlet.class);

    /**
     * The path to search.
     */
    private static final String SEARCH_PATH = "/content/my/website/data";

    /**
     * The JSON indentation level.
     */
    private static final int JSON_INDENTATION_LEVEL = 4;

    /**
     * The method called by the get.
     * {@inheritDoc}
     */
    @Override
    protected void doGet(final SlingHttpServletRequest request, final SlingHttpServletResponse response) throws ServletException, IOException
    {
        // Get the properties that have been requested
        final Map<String, Object> map = new HashMap<>();
        map.put("type", "nt:unstructured");
        map.put("path", SEARCH_PATH);

        map.put("1_property", "current");
        map.put("1_property.value", true);

        // Get the QueryBuilder and do the query from the Map above.
        final Session session = request.getResourceResolver().adaptTo(Session.class);
        final QueryBuilder builder = request.getResourceResolver().adaptTo(QueryBuilder.class);
        final Query query = builder.createQuery(PredicateGroup.create(map), session);
        query.setHitsPerPage(Integer.MAX_VALUE);
        final SearchResult result = query.getResult();

        // Iterate over the results
        final Iterator<Resource> resources = result.getResources();
        try
        {
            while (resources.hasNext())
            {
                // Get the next resource, convert to Node and make it as JSON.
                final Resource resource = resources.next();
                final Node node = resource.adaptTo(Node.class);
                final JsonJcrNode jsonJcrNode = new JsonJcrNode(node, getNodeIgnoreSet());
                response.getOutputStream().println(jsonJcrNode.toString(JSON_INDENTATION_LEVEL));
            }
        }
        catch (final RepositoryException | JSONException e)
        {
            response.getOutputStream().println("Error iterating over the results " + e.getMessage());
            LOG.error("Error iterating over the search results", e);
        }

        response.flushBuffer();
    }
}

Unit Test

The unit test uses AemContext to set up a load of mocks which are needed for the test.  However, the AemContext does not give a QueryBuilder object out of the box so an adapter has to be defined for this.  It is added to the AemContext.

import static org.junit.Assert.assertTrue;
import static org.mockito.Matchers.any;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.jcr.Session;
import javax.servlet.ServletException;

import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.resource.ResourceResolver;
import org.apache.sling.testing.mock.sling.ResourceResolverType;
import org.apache.sling.testing.mock.sling.servlet.MockSlingHttpServletRequest;
import org.apache.sling.testing.mock.sling.servlet.MockSlingHttpServletResponse;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mock;
import org.mockito.runners.MockitoJUnitRunner;

import com.day.cq.search.PredicateGroup;
import com.day.cq.search.Query;
import com.day.cq.search.QueryBuilder;
import com.day.cq.search.result.SearchResult;

import io.wcm.testing.mock.aem.junit.AemContext;

/**
 * Test class for the {@link SearchCurrentServlet}.
 */
@RunWith(MockitoJUnitRunner.class)
public class SearchCurrentServletTest
{
    /**
     * The mocked query builder.
     */
    @Mock
    private QueryBuilder queryBuilder;

    /**
     * The AEM context to test with.
     */
    @Rule
    public final AemContext context = new AemContext(aemContext ->
    {
        aemContext.load().json("/result.json", "/result.json");
        aemContext.registerAdapter(ResourceResolver.class, QueryBuilder.class, queryBuilder);
    }, ResourceResolverType.JCR_MOCK);

    /**
     * Test the output in json includes fields from the node.
     *
     * @throws IOException thrown by the servlet method
     * @throws ServletException thrown by the servlet method
     */
    @Test
    public void testDoGet() throws ServletException, IOException
    {
        // Arrange
        final SearchCurrentServlet servlet = new SearchCurrentServlet();
        final MockSlingHttpServletRequest request = context.request();
        final MockSlingHttpServletResponse response = context.response();

        final Query query = mock(Query.class);
        final SearchResult searchResult = mock(SearchResult.class);
        final Resource resource = context.currentResource("/result.json");
        final List<Resource> results = new ArrayList<>();
        results.add(resource);

        when(queryBuilder.createQuery(any(PredicateGroup.class), any(Session.class))).thenReturn(query);
        when(query.getResult()).thenReturn(searchResult);
        when(searchResult.getResources()).thenReturn(results.iterator());

        // Act
        servlet.doGet(request, response);

        // Assert
        // System.out.println(response.getOutputAsString());
        assertTrue(response.getOutputAsString().contains("\"name\": \"Bob\""));
        assertTrue(response.getOutputAsString().contains("\"cost\": \"12.34\""));
    }
}

Unit Test Data

The AemContext loads a json file from src/test/resources (the classpath) and makes it available for the path specified.  When the resource is loaded with context.currentResource("/result.json"); the Resource object returned is made up of the values in the result.json file.

result.json has only the following lines

{
"jcr:primaryType":"nt:unstructured",
        "current":true,
        "name":"Bob",
        "cost":12.34
}

AEM Multifield for Touch UI Dialogs

Multifields are used to group at field set together within AEM.  In a dialog they can be used to store a variable sized array or create a node hierarchy.

Single Field

For a single field the set up is very simple.  The field that can be added and removed is just put straight under the multifield value,


  <description-lines
    jcr:primaryType="nt:unstructured"
    sling:resourceType="granite/ui/components/foundation/form/multifield"
    fieldLabel="Description Lines"
    renderReadOnly="{Boolean}true">
    <field
      jcr:primaryType="nt:unstructured"
      sling:resourceType="granite/ui/components/foundation/form/textfield"
      name="./descriptionLines"/>
  </term-description>

This multifield will store an array of the values entered into the ./descriptionLines value in the JCR.

Field Set

For a genuine set of fields that need to be grouped together the hierarchy under the multifield definition is more complicated,

  <person
    jcr:primaryType="nt:unstructured"
    sling:resourceType="/apps/touch-ui-multi-field-panel/multifield"
    class="full-width"
    fieldDescription="Click '+' to add a new person"
    fieldLabel="People">
    <field
      jcr:primaryType="nt:unstructured"
      sling:resourceType="granite/ui/components/foundation/form/fieldset"
      name="./items">
      <layout
        jcr:primaryType="nt:unstructured"
        sling:resourceType="granite/ui/components/foundation/layouts/fixedcolumns"
        method="absolute"/>
      <items jcr:primaryType="nt:unstructured">
        <column
          jcr:primaryType="nt:unstructured"
          sling:resourceType="granite/ui/components/foundation/container">
          <items jcr:primaryType="nt:unstructured">
            <name
              jcr:primaryType="nt:unstructured"
              sling:resourceType="granite/ui/components/foundation/form/textfield"
              fieldDescription="Enter Name"
              fieldLabel="Name"
              name="./name"/>
            <age
              jcr:primaryType="nt:unstructured"
              sling:resourceType="granite/ui/components/foundation/form/textfield"
              fieldDescription="Enter Age"
              fieldLabel="Age"
              name="./age"/>
          </items>
        </column>
      </items>
    </field>
  </person>

This multifield creates a subnode under ./items each of which contains a 'name' and 'age' field as defined as textfields in the set up.